graham



I A. T. GRAHAM.

; DENTAL IMPRESSION TRAY.

APPLICATION FILED APR.26| 19 20.

:1,36'9,'1 71 PatentedFeB. 22,1921.

2 SHEETS-SHEET I NV ENTOR.

. flrur TGr a ham A. T. GRAHAM. DENTAL IMPR ESSION TRAY.

APPLICATION. FILED APR.26. I920- 1, 36 9,171. Patented Feb. 22, 1921.

2 SHEETS-SHEET 2.

INVENTOR.

.%MZ W ATT NEY.

UNITED STATES PATENT OFFICE.

ARTHUR T. GRAHAM, OF SAN FRANCISCO, CALIFORNIA..

. I DENTAL IMPRESSION-TRAY.

' "a li ation filed April as,

To all whom-it may concern: I I

Be it known that I, AirrHUR IT. GRAHAM, a citizen of the llnite'd States, residing at San Franc'isco,-in the county of San'Fran cisco, State of California, have invented a new and useful Dental Impression-Tray, of

which the following is a specification in such full and clear'terms as will enable those skilled in the art to construct and use the same. 7 4 V V This invention relates to a dental impression tray and its object is to provide means whereby an impression er the upper and lower teeth or the upper and lower gums may be taken at one time, the tray being separable to enable the dentist to remove the plaster cast containing the upper impression independently of the lowerimpression. It will be understood 'by'those skilled in the art that in taking-the impression of teeth for the production of false teeth or for the production of plates carrying false teeth, that it is necessary to provide means whereby the plaster mold showingthe exact shape of the gums'orteeth may be produced.

This mold mustbe left in the mouth for a sutliciently long time to permit the plaster to set, or if wax'compound is used it must be allowedto set arid then considerable difli culty is found in removing the mold from the teeth without injuring the mold.

In'the presentinstance the tray is separable intojtwo. parts and when the plaster or wax for taking'the impression is; placed in the tray, a sheet of paper or tin foil is placed between the two sections of the tray to prevent the plaster'or wait on the top portion of the trayfrom adhering to the plaster'or wax in the lower. portion ot'the tray. vSo that when the impression'is taken and the plaster or wax is hardened, a latch holding the tray together may be released and the two parts of the tray separated fronrone another, therebymakingit much easier to remove the tray from the teeth than it would be where the upper and. lower teeth are embedded in a. single body of was; or plaster. In the latter instance the tray must be worked loose from the upper set of teeth first and thereafter the tray .is worked loose from the lower setof teeth.

Other objects ofthe invention will appear as the description proceeds.

An embodiment of the invention is shown in the accompanying drawings in which the Specification .of Letters Patent.

Patented Feb. 22, 1921. 1920. Serial No. 376,607.

same reference numeral is applied to the same portion throughout, but I am aware that there may be modifications thereof.

7 Figure 1 is a side elevation of the tray as it is used for taking an impression of the teeth on one'side of the mouth, both the upper and lower sections being connected together. I Fig.2is a of the tray.

Fig. 3 is a plan view of the upper portion of the trayfi. 1

Fig. 4: is a side elevation of one side of the tray, the connecting bar being shown in section on the plane 44 Fig. 3

Fig. 5 is a side elevation of the lower poition of the tray on the plane 55 Fig. 2.

Fig. 6 is a plan view of the tray as it is used for taking a full month impression, both the upper and lower sections being connected together. I

Fig. 7 is a side elevation of the tray shown in Fig. 6. j

Fig. 8 is a plan view of a tray used for taking an impression of the front teeth only,

plan view of the lower portion both the upper andflower sections being.

connect-ed together.

Fig. 9 is a side elevation of shown in Fig. 8. I

Figs' 10 and lliare perspective views showing the tray in use.

' The tray is formed in two separable parts, the lowero'f'which has a handle portion 1; with two depending substantially parallel wings 2 and 3 connected together by the hollow bar 4. A wire rod 5 extends through the bar and it has curved portions 6 and 7 which are positioned to overlie the laterally extending flanges or members 8 and 9 of the upper portion of the tray.

' An extension 10 of the rod 5 may be placed under a st-ifl spring 11 secured at one end to the handle 1, to hold the rod 5 in the position shown in Fig. 2 for the purpose of looking the two portions of the tray together as will be presently explained.

The upper portion of the tray has two wings'12 and 13, which when the tray is secured together form extensions of the planes ofthe wings 2 and 3 and they are connected together by means of a cross-bar 14,, which is recessed to allow'the cross-bar 4 to fit thereinto.

The laterally extending wings 8 and 9 of the upper member are slotted as indicated at the tray 15 and 16 to permit the portions 7 and 8 of the rod to pass therethrough to lock the two portions of the tray together, as indicated in Fig. 1.

The spring 11 bears upon the extension 10 to hold the two portions of the tray locked.

In the form of the invention shown in Figs. 6 and 7, the tray has the handle 17, which handle is connected to a portion 18 shaped to fit the inside of the mouth, inside and outside the teeth on both sides of the mouth.

This member 18 is connected by two bars 19 and 20 to a curved member 21, which is shaped to fit inside the teeth on both sides. The bars 19 and 20 have rods 22 and 23 extending therethrough respectively, the same as the bar 4 and rod 5, and said rods have curved portions 24: to 27 inclusive which are adapted to overlie the laterally extending flanges 28 to 31 of the upper member.

The upper member is provided with one long curved flange 32 which is connected to an'upwardly extending flange 33 as long as the combined length of the flanges 28, 31 and 32 and it is connected by means of two cross-bars 34 and 35 to the inner flange member 36.

The upper and lower members of the tray are locked together by the springs 37 and 38, which are secured to the lower member of the tray and the ends of which may be placed over the ends of 39 and 40 of the rods 22 and 23 to hold the two trays together as shown in Fig. 7

In the form of the invention shown in Figs. 8 and9, the two trays are of a suitable shape to take an impression of the front teeth only. The lower tray has a handle 50, on one end of which there is a curved lower tray 51 with'the cross-bar 52 connecting the front tray portion 51 with the back curved tray portion 52, which is shaped to lie within the front teeth. The upper portion of the tray is separable from the lower portion precisely the same as the previous forms of the invention and has the front flange 53, which is connected to the rear flange 54 by the bar 55, which fits over the bar 52. Extending through the bar 52 is the rod 56, which has a portion 57 and portion 58 bent to overlie the horizontal portions of the flanges 53 and 54 to hold the two portions of the tray together.

A spring 59 on the handle 50.is positioned to bear upon an extension 60 of the rod 56 to hold the two portions of the tray locked together.

The operation of the apparatus is as follows: The two parts of the tray are secured together. with a strip of paper or tin foil between the two tray members. The plaster or wax is then placed above and below the strip of paper or tin foil between the flanges 2, 3, 12 and 13. The impression is then 6% taken and allowed to harden. As soon as the plaster or wax has hardened sufliciently the spring 11 is released from the locked po sition to allow the connecting rod 5 to turn so the trays may be separated. The patient may then open his mouth wide enough to permit the impressions to be removed from the teeth one at a time and with such care as is necessary to prevent injuring them.

What I claim is as follows, but various modifications may be made in the construction shown in the drawings and above particularly described form, within the purview of my invention: 7

1. A dental appliance comprising an upper and lower tray each having flanges extending substantially parallel to the length of the teeth adapted to hold materials for forming an impression of teeth and means to detachably connect the two portions of the trays rigidly together whereby the upper impression may be separated from the lower impression.

2. A dental appliance comprising an upper and lower tray each having spaced flanges adapted to lie substantially parallel to the length of the teeth for holding a ma terial to take an impression of teeth, a latch for holding the two portions of the trays rigidly together and a spring for retaining the latch in the locked position.

3. Adental appliance comprising an upper and lower tray, each tray having two connected spaced flanges which are alined when the trays are secured together, a pivoted latch for. securing the two trays together and a spring for holding said latch in the locked position.

4. A dental appliance comprising an upper and lower tray, each of which has two connected flanges, which flanges are alined in pairs when the trays are secured together, a pivoted latch having means adjacent each flange for holding the trays to gether and a spring for holding said latch in 11 a a locked position.

5. A dental appliance comprising'an upper and lower tray, each tray having two flanges connected with a transverse hollow bar, a pivoted latch extending through said bar and adapted to secure the two portions of the appliance rigidly together and a spring for holding the latch in the locked position.

In testimony whereof I have hereunto set my hand this 16th day of April, A. D. 1920.

ARTHUR T. GRAHAM. 

